The present invention relates to a bumper reinforcement to be placed within a bumper face in bumpers of vehicles, such as automobiles.
As the bumper structure for vehicles such as automobiles, there has conventionally been widely well known a bumper structure in which a bumper reinforcement as a reinforcing member is placed inside the bumper face and between them is disposed an impact energy absorber made of, for example, urethane resin foaming material or the like.
In recent years, with a view to reducing the parts count and thereby realizing the simplification of the structure, as well as reducing manufacturing cost, it has also been under consideration to impart impact energy absorbency to a bumper reinforcement and make up a bumper from this reinforcement and the bumper face. In this case, generally, the bumper reinforcement is formed from synthetic resin.
As a bumper of this type, for example, Japanese Utility Model Laid-Open Publication SHO 63-166855 has disclosed a bumper in which the bumper reinforcement is formed into a U shape in its cross section and placed on the rear face side of the bumper face with the open end side of the U shape directed forward, where the two members are fixed to each other with adhesive.
However, if the bumper face and the bumper reinforcement are adhesively fixed as in the above conventional case, there would be disadvantages such as needing a time consuming bonding process, which requires drying time of adhesive. Moreover, the whole bumper including the bumper reinforcement, needs to be replaced even when only the bumper face is damaged. Further, because a metallic bracket for use of mounting the bumper reinforcement to vehicle-body side members generally needs to be preliminarily provided inside the bumper reinforcement and this metallic bracket could not be removed even at disposal of the bumper reinforcement, the bumper reinforcement formed from synthetic resin would result in poor recyclability another disadvantage.
As to the bumper performance at a collision of the vehicle, when a collision load is input to the bumper face, the less backward displacement of the bumper reinforcement rear face (in particular, the rear face of central portion in the direction of vehicle width) is preferable in terms of the protection of the vehicle body. For example, in the legal regulations of the United States, so-called pendulum tests are provided in PART 581.
Under the circumstance that the structure for improving such performance has been being discussed in various ways, there is a need for a bumper reinforcement without any complication of the prior art structure and increased manufacturing cost and the like.